Hi.
Thanks for reporting, but that's intended behaviour.
Quickmesh can display massive amounts of polygons with some limitations. You do not want to collapse those limitations to mesh object.
Even if collapsed to mesh object it's very likely 3ds max would run out of RAM. You don't want that too.
If object can be displayed in MeshMode then this is more advisable than QuickMesh as it has some limitations. Quick mesh is meant for massive polygon counts.
You can use RailClone Tools utility with correct results even in QuickMesh mode: